title: Multiply protonated betaine clusters are stable in the gas phase.
abstract: Multiply protonated clusters of betaine are formed via electrospray ionisation and fragment via competitive betaine neutral loss and charge separation; theoretical calculations suggest the [M(n)+2H](2+) ions consist of a [M(2)+2H](2+) core based on the hydrogen bonded carboxylic acid dimer.
authors.affiliation: School of Chemistry, University of Melbourne, Victoria 3010, Australia.
authors.forename: Linda
authors.initials: L
authors.lastname: Feketeová
authors.forename: Richard A J
authors.initials: RA
authors.lastname: O'Hair
mesh_terms: D001622:Betaine / Q000737:chemistry*; D005740:Gases / Q000737:chemistry*; D007536:Isomerism; D011522:Protons; D011789:Quantum Theory; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D005740:Gases; D011522:Protons; D001622:Betaine